1. Field of the Invention
This invention relates to a fodder conditioner, also called a "fodder squeezer".
2. Description of the Prior Art
Known are agricultural implements called fodder conditioners or fodder squeezers, which are intended to make the drying rates of the various parts encompassed by the term "fodder" more uniform, and specifically to accelerate the drying process of the largest parts thereof (mainly made up of stems) with respect to the smallest parts (mainly made up of leaves). In this manner, the overall drying time of fodder can be shortened. This cutting down of drying time can be of the order of up to 30-50 percent, that is of such a magnitude as to materially affect the processing cost.
Further, concurrent drying of stems and leaves prevents the latter, which dry up more quickly, from separating from the former and becoming a loss so as to deprive the fodder of its nutritional and organoleptic properties.
To achieve such results, the state-of-the-art provides conditioning, or squeezing, devices which comprise essentially a pair of squeezing rollers or cylinders, in the nip of which freshly mowed fodder is fed. The thusly conditioned fodder is then spread again over the ground to complete its drying. The pair of squeezing rollers provided by the state of the art are essentially of three different types, namely:
(1) smooth, mostly steel, rollers, at least one of which may be coated with a resilient material (rubber) and/or formed with surface grooves or ribs to improve its hold on fodder. The bearings of at least one of the two squeezer rollers are mounted in adjustable elastic supports to enable changing both the axis spacing and pressure exerted between the two rollers by the springs of the elastic supports, so as to adjust said pressure for the characteristics of the fodder to be conditioned and to cope with the presence therein of such hard foreign matter (branches, stones, dirt) as may forcibly widen the spacing of the rollers.
(2) toothed rollers, meshing together like a gear pair, through the nip whereof fodder is caused to pass for processing.
(3) a smooth, mostly rubber-coated, steel roller and a toothed roller, also of steel, with characteristics complementary to the former.
The above-cited advantages of prior fodder conditioning processes are accompanied by some problems, which the three types of conventional conditioners just described can only partly obviate.
In fact, a really effective squeezing action on fodder stems is only applied by the first-mentioned conditioner type having smooth rollers, whereas the one of the second-mentioned type can do no better than bend the stems. On the other hand, the conditioner of the first-mentioned type requires that both rollers be driven directly and since one of them must include movable supports for spacing adjustment purposes, as mentioned above, its drive system is made more complicated. It is common practice to use a belt drive with a tightener, either of the chain or gear type, which is accompanied by well-known drawbacks brought about by wear, the need to apply constant adjustment and maintenance, inertia of parts undergoing sharp displacement movements (movable support roller and tightener) upon the appearance of branches or stones between the rollers, or the need to merely adjust the roller spacing to accommodate changes in the flow rate of the fodder picked up from the ground.
This increased complication of a mechanical nature is accompanied by an increase in the mechanical stresses, which make necessary the adoption of drive protecting devices such as a coupling or safety pin to prevent damage and breakage. Such protective measures can only partly solve the problem, because in the event of a corrective action, they would add to the downtime of the production process for their replacement. Furthermore, the transmission of motion to a rotary element with movable supports is known to imply a decreased drive efficiency and hence a higher energy consumption.
With the conventional conditioner, direct motion transmission can be limited to the fixed support roller alone, but the suitability of this approach is offset by the reduced efficiency of the squeezing action. Further, the likelihood of jamming and breakage from foreign matter is not eliminated.
The third type of prior conditioner is a compromise of the former two and requires driving both rollers similarly to the first type.
A further drawback shared by the three prior types of conditioners is that the arrangement for adjusting the pressure between the rollers does not remove non-uniformity between the pressure applied on the middle, thicker portion of the fodder layer between the rollers, and the pressure on the side portions, of smaller thickness. This results in incomplete conditioning of the side portions, or excessive squeezing of the moddle portions.